1
|
Feng W, Liu Z, Ye M. Liquid crystal lens with a shiftable optical axis. OPTICS EXPRESS 2023; 31:15523-15536. [PMID: 37157652 DOI: 10.1364/oe.488844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
A liquid crystal (LC) lens with a laterally shiftable optical axis is proposed and demonstrated. The optical axis of the lens can be driven to shift within the lens aperture without compromising its optical properties. The lens is constructed by two glass substrates with identical interdigitated comb-type finger electrodes on the inner surfaces, and they are oriented at 90° with respect to each other. The distribution of voltage difference between two substrates is determined by eight driving voltages, and is controlled within the linear response region of LC materials, thereby generating a parabolic phase profile. In experiments, an LC lens with an LC layer of 50 µm and an aperture of 2 mm × 2 mm is prepared. The interference fringes and focused spots are recorded and analyzed. As a result, the optical axis can be driven to shift precisely in the lens aperture, and the lens maintains its focusing ability. The experimental results are consistent with the theoretical analysis, and good performance of the LC lens is demonstrated.
Collapse
|
2
|
Wang F, Zhuang Z, Qin Z, Wen B. Movable and Focus-Tunable Lens Based on Electrically Controllable Liquid: A Lattice Boltzmann Study. ENTROPY (BASEL, SWITZERLAND) 2022; 24:1714. [PMID: 36554119 PMCID: PMC9777668 DOI: 10.3390/e24121714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/13/2022] [Accepted: 11/21/2022] [Indexed: 06/17/2023]
Abstract
Adjusting the focal length by changing the liquid interface of the liquid lens has become a potential method. In this paper, the lattice-Boltzmann-electrodynamic (LB-ED) method is used to numerically investigate the zooming process of a movable and focus-tunable electrowetting-on-dielectrics (EWOD) liquid lens by combining the LBM chemical potential model and the electrodynamic model. The LB method is used to solve the Navier-Stokes equation, and the Poisson-Boltzmann (PB) equation is introduced to solve the electric field distribution. The experimental results are consistent with the theoretical results of the Lippmann-Young equation. Through the simulation of a liquid lens zoom driven by EWOD, it is found that the lens changes from a convex lens to a concave lens with the voltage increases. The focal length change rate in the convex lens stage gradually increases with voltage. In the concave lens stage, the focal length change rate is opposite to that in the convex lens stage. During the zooming process, the low-viscosity liquid exhibits oscillation, and the high-viscosity liquid appears as overdamping. Additionally, methods were proposed to accelerate lens stabilization at low and high viscosities, achieving speed improvements of about 30% and 50%, respectively. Simulations of lens motion at different viscosities demonstrate that higher-viscosity liquids require higher voltages to achieve the same movement speed.
Collapse
Affiliation(s)
- Fei Wang
- Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China
- School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China
| | - Zijian Zhuang
- Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China
- School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China
| | - Zhangrong Qin
- Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China
- School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China
| | - Binghai Wen
- Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China
- School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China
| |
Collapse
|
3
|
Feng W, Liu Z, Ye M. Liquid crystal lens array with positive and negative focal lengths. OPTICS EXPRESS 2022; 30:28941-28953. [PMID: 36299080 DOI: 10.1364/oe.464526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 07/10/2022] [Indexed: 06/16/2023]
Abstract
A positive-negative tunable liquid crystal lens array is proposed by electrode design. The electrode structure consists of two main units, one of them is used to generate parabolic voltage profile and the other one distributes the voltage homogeneously across the lens aperture. The proposal features the advantages of high-quality performance, simple fabrication process (a single lithographic step), compact design, low voltages and simple driving method. In addition, the lens array can be driven as a square lens array or a rotatable cylindrical lens array. The voltage difference between the electrodes on the inner face of two substrates is controlled within the range that the phase of liquid crystal layer responds linearly to voltage difference, then the phase of the lens array maintains parabolic profile in the whole focus range. In experiments, a lens array with 30 µm liquid crystal layer is fabricated using the designed electrode. The size of the array area is 11 × 11 mm, and the side length of an individual square lens is 1.0 mm. The results show that the phase profile matches with the parabolic profile during focus tuning, and good focusing effect of the positive lens is observed. As a result, a liquid crystal lens array with high-quality performance is experimentally demonstrated, and the experimental results are consistent with the theoretical analyses.
Collapse
|
4
|
Chu F, Guo YQ, Zhang YX, Duan W, Zhang HL, Tian LL, Li L, Wang QH. Four-mode 2D/3D switchable display with a 1D/2D convertible liquid crystal lens array. OPTICS EXPRESS 2021; 29:37464-37475. [PMID: 34808817 DOI: 10.1364/oe.441386] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 10/21/2021] [Indexed: 05/28/2023]
Abstract
A four-mode 2D/3D switchable display using a 1D/2D convertible liquid crystal (LC) lens array is proposed in this paper. The LC lens array is composed of two orthogonal LC lens arrays, with a λ/2 film in the middle to rotate the polarization by 90°. Based on the LC lens array, a four-mode 2D/3D switchable display is realized, which is switchable between the turn-off and turn-on states: when the operating voltage V1 = 0, V2 = 0, the display operates in mode I, which is 2D display; when the operating voltage V1 = 0, V2 = 0, the display operates in mode II, and the 3D display effect is in x direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode III, and the 3D display effect is in y direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode IV, the 3D display effect is in x-y plane. Experimental results indicate that the LC lens array has simple fabrication process, low operating voltage (∼5.4V), and short focal length. Moreover, based on the designed LC lens array, the 2D/3D switchable display shows no moiré pattern.
Collapse
|
5
|
Abstract
We propose a multi-view 2D/3D switchable display by using cylindrical liquid crystal (LC) lens array with a low operating voltage and fast response time. The cylindrical LC lens array is composed of three parts: the LC layer, a top-plane indium tin oxide (ITO) electrode, and bottom periodic strip ITO electrodes. In the voltage-off state, the cylindrical LC lens array is equivalent to a transparent glass substrate and the viewers can see a clear 2D image. In the 3D mode, the cylindrical LC lens array can be used as a cylindrical lens array under a suitable operating voltage. As a result, the 2D and 3D images can be switched according to the state of the cylindrical LC lens array. The experimental result shows that the 2D/3D switchable display with the cylindrical LC lens array has a wider viewing angle, has no moiré pattern, and is much thinner compared to the other 2D/3D switchable display devices.
Collapse
|
6
|
Morris R, Jones C, Nagaraj M. Liquid Crystal Devices for Beam Steering Applications. MICROMACHINES 2021; 12:247. [PMID: 33671001 PMCID: PMC7997246 DOI: 10.3390/mi12030247] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/22/2021] [Accepted: 02/23/2021] [Indexed: 11/17/2022]
Abstract
Liquid crystals are valuable materials for applications in beam steering devices. In this paper, an overview of the use of liquid crystals in the field of adaptive optics specifically for beam steering and lensing devices is presented. The paper introduces the properties of liquid crystals that have made them useful in this field followed by a more detailed discussion of specific liquid crystal devices that act as switchable optical components of refractive and diffractive types. The relative advantages and disadvantages of the different devices and techniques are summarised.
Collapse
Affiliation(s)
| | | | - Mamatha Nagaraj
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK; (R.M.); (C.J.)
| |
Collapse
|
7
|
Switchable Lens Design for Multi-View 2D/3D Switching Display with Wide-Viewing Window. CRYSTALS 2020. [DOI: 10.3390/cryst10050418] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We improved the three-dimensional (3D) crosstalk level of multi-view 3D displays using a lens array with small f-number, thereby facilitating a wide 3D viewing window. In particular, we designed a polarization-dependent-switching liquid crystal (LC)-based gradient refractive index (GRIN) lens array that could be switched between 2D and 3D viewing modes. For the GRIN lens with a small f-number (1.08), we studied the effect of the interfacial curvature between the plano-concave isotropic polymer layer and the plano-convex birefringent LC layer on the aberration properties. We examined the conventional spherical, quadratic polynomial aspherical, and a high-order (fourth-order) polynomial aspherical curvature. For the high-order polynomial aspherical curvature, the achievable transverse spherical aberration (TSA = 10.2 µm) was considerably lower than that with the spherical (TSA = 100.3 µm) and quadratic polynomial aspherical (TSA = 30.4 µm) curvatures. Consequently, the angular luminance distributions for each view were sharper for the high-order polynomial interfacial curvature. We designed multi-view (43-view) 3D displays using the arrays of switchable LC lenses with different curvatures, and the average adjacent crosstalk levels within the entire viewing window (50°) were 68.5%, 73.3%, and 60.0% for the spherical, quadratic polynomial aspherical, and high-order polynomial aspherical curvatures, respectively.
Collapse
|
8
|
Song X, Zhang H, Li D, Jin Q, Jia D, Liu T, Wang C. Liquid Lens with Large Focal Length Tunability Fabricated in a Polyvinyl Chloride/Dibutyl Phthalate Gel Tube. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:1430-1436. [PMID: 31971397 DOI: 10.1021/acs.langmuir.9b03585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Usually, an adaptive liquid lens only has a positive focal length, which severely limits its application in imaging and other fields. Therefore, a liquid lens consisting of polyvinyl chloride/dibutyl phthalate (PVC/DBP) gel, glycerol solution, and a glass substrate is proposed to extend the dynamic focal length range. A spherical tube is formed by the PVC/DBP gel under the effect of hydrostatic and surface tensions, which is used to restrict the glycerol solution. The PVC/DBP gel does not deform under the effect of an electric field, so the tangent line at the three-phase junction changes with the change of contact angle, which leads to an enlargement of the dynamic focal length range. At different voltage values, the proposed lens can be configured to work in three different schemes, namely, converging light, nondeflecting light, and diverging light. Here, the proposed lens has high imaging quality; the resolution is better than 114 lp/mm. A lens with a reconfigurable focal length holds great promise in diverse applications such as fluorescence detection, beam shaping, and adaptive optics.
Collapse
Affiliation(s)
- Xiaomin Song
- College of Precision Instrument and Optoelectronics Engineering , Tianjin University , Tianjin 300000 , China
- Key Laboratory of Optoelectronics Information Technical Science , EMC, Tianjin 30000 , China
| | - Hongxia Zhang
- College of Precision Instrument and Optoelectronics Engineering , Tianjin University , Tianjin 300000 , China
- Key Laboratory of Optoelectronics Information Technical Science , EMC, Tianjin 30000 , China
| | - Dongyang Li
- College of Precision Instrument and Optoelectronics Engineering , Tianjin University , Tianjin 300000 , China
- Key Laboratory of Optoelectronics Information Technical Science , EMC, Tianjin 30000 , China
| | - Qingwen Jin
- College of Precision Instrument and Optoelectronics Engineering , Tianjin University , Tianjin 300000 , China
- Key Laboratory of Optoelectronics Information Technical Science , EMC, Tianjin 30000 , China
| | - Dagong Jia
- College of Precision Instrument and Optoelectronics Engineering , Tianjin University , Tianjin 300000 , China
- Key Laboratory of Optoelectronics Information Technical Science , EMC, Tianjin 30000 , China
| | - Tiegen Liu
- College of Precision Instrument and Optoelectronics Engineering , Tianjin University , Tianjin 300000 , China
- Key Laboratory of Optoelectronics Information Technical Science , EMC, Tianjin 30000 , China
| | - Chao Wang
- School of Engineering and Digital Arts , University of Kent , Canterbury , Kent CT2 7NT , U. K
| |
Collapse
|
9
|
He Z, Lee YH, Chanda D, Wu ST. Adaptive liquid crystal microlens array enabled by two-photon polymerization. OPTICS EXPRESS 2018; 26:21184-21193. [PMID: 30119422 DOI: 10.1364/oe.26.021184] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 07/23/2018] [Indexed: 06/08/2023]
Abstract
A tunable-focus liquid crystal microlens array is demonstrated and characterized. Using two-photon polymerization based direct-laser writing, a polymerized microlens array is fabricated on one substrate. Such a microlens array creates inhomogeneous electric field distribution and homogeneous-like liquid-crystal alignment, simultaneously. The phase profile and thus the focal length can be tuned dynamically by the applied voltage. We also further investigate the focusing property and the imaging capability of the fabricated sample. Using the adaptive microlens array as an example, we demonstrate that directly forming a curvilinear surface with liquid-crystal alignment is feasible. In addition to adaptive lens, this direct-laser writing method is also a powerful tool for making other tunable photonic devices.
Collapse
|
10
|
Dou H, Chu F, Guo YQ, Tian LL, Wang QH, Sun YB. Large aperture liquid crystal lens array using a composited alignment layer. OPTICS EXPRESS 2018; 26:9254-9262. [PMID: 29715879 DOI: 10.1364/oe.26.009254] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 03/22/2018] [Indexed: 06/08/2023]
Abstract
A liquid crystal (LC) lens array with high light control power and a large aperture using a composited alignment layer is proposed. In our design, the alignment layer is not only used for getting a uniform arrangement of LC molecule, but also for getting a lens-like refractive index distribution in the LC layer when a voltage is applied. Through simple technology processes, a tunable focal length LC lens array with a millimeter scale diameter can be achieved. Furthermore, the maximum phase difference of the proposed LC lens array can achieve 105.38π. So, the proposed LC lens array has a high light control power.
Collapse
|
11
|
Shi L, Srivastava AK, Wai Tam AM, Chigrinov VG, Kwok HS. 2D-3D switchable display based on a passive polymeric lenticular lens array and electrically suppressed ferroelectric liquid crystal. OPTICS LETTERS 2017; 42:3435-3438. [PMID: 28957056 DOI: 10.1364/ol.42.003435] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 07/31/2017] [Indexed: 06/07/2023]
Abstract
We reveal a 2D-3D switchable lens unit that is based on a polarization-sensitive microlens array and a polarization selector unit made of an electrically suppressed helix ferroelectric liquid crystal (ESHFLC) cell. The ESHFLCs offer a high contrast ratio (∼10k∶1) between the crossed polarizers at a low applied electric field (∼1.7 V/μm) with a small switching time (<50 μs). A special driving scheme, to switch between a 2D and 3D mode, has been developed to avoid unwanted issues related to DC accumulation in the ferroelectric liquid crystal without affecting its optical quality. The proposed lens unit is characterized by low power consumption, ultrafast response, and 3D crosstalk <5%, and can therefore find application in TVs, cell phones, etc.
Collapse
|
12
|
Lei Y, Tong Q, Xin Z, Wei D, Zhang X, Liao J, Wang H, Xie C. Three dimensional measurement with an electrically tunable focused plenoptic camera. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:033111. [PMID: 28372436 DOI: 10.1063/1.4979027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A liquid crystal microlens array (LCMLA) with an arrayed microhole pattern electrode based on nematic liquid crystal materials using a fabrication method including traditional UV-photolithography and wet etching is presented. Its focusing performance is measured under different voltage signals applied between the electrodes of the LCMLA. The experimental outcome shows that the focal length of the LCMLA can be tuned easily by only changing the root mean square value of the voltage signal applied. The developed LCMLA is further integrated with a main lens and an imaging sensor to construct a LCMLA-based focused plenoptic camera (LCFPC) prototype. The focused range of the LCFPC can be shifted electrically along the optical axis of the imaging system. The principles and methods for acquiring several key parameters such as three dimensional (3D) depth, positioning, and motion expression are given. The depth resolution is discussed in detail. Experiments are carried out to obtain the static and dynamic 3D information of objects chosen.
Collapse
Affiliation(s)
- Yu Lei
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qing Tong
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhaowei Xin
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Dong Wei
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xinyu Zhang
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jing Liao
- Wuhan Product Quality Supervision and Test Institute, Wuhan 430048, China
| | - Haiwei Wang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Changsheng Xie
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
| |
Collapse
|
13
|
Kang S, Zhang X. Compound liquid crystal microlens array with convergent and divergent functions. APPLIED OPTICS 2016; 55:3333-3338. [PMID: 27140107 DOI: 10.1364/ao.55.003333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/17/2016] [Indexed: 06/05/2023]
Abstract
Based on the common liquid crystal microlens, a new compound structure for a liquid crystal (LC) microlens array is proposed. The structure consists of two sub LC microlens arrays with properties of light divergence and convergence. The structure has two LC layers: one to form the positive sub lens, one for the negative. The patterned electrode and plane electrode are used in both sub microlens arrays. When two sub microlens arrays are electrically controlled separately, they can diverge or converge the incident light, respectively. As two sub microlens arrays are both applied on the voltage, the focal length of the compound LC microlens becomes larger than that of the LC microlens with a single LC layer. Another feature of a compound LC microlens array is that it can make the target contour become visible under intense light. The mechanisms are described in detail, and the experimental data are given.
Collapse
|
14
|
Lei Y, Tong Q, Zhang X, Sang H, Ji A, Xie C. An electrically tunable plenoptic camera using a liquid crystal microlens array. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:053101. [PMID: 26026508 DOI: 10.1063/1.4921194] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Plenoptic cameras generally employ a microlens array positioned between the main lens and the image sensor to capture the three-dimensional target radiation in the visible range. Because the focal length of common refractive or diffractive microlenses is fixed, the depth of field (DOF) is limited so as to restrict their imaging capability. In this paper, we propose a new plenoptic camera using a liquid crystal microlens array (LCMLA) with electrically tunable focal length. The developed LCMLA is fabricated by traditional photolithography and standard microelectronic techniques, and then, its focusing performance is experimentally presented. The fabricated LCMLA is directly integrated with an image sensor to construct a prototyped LCMLA-based plenoptic camera for acquiring raw radiation of targets. Our experiments demonstrate that the focused region of the LCMLA-based plenoptic camera can be shifted efficiently through electrically tuning the LCMLA used, which is equivalent to the extension of the DOF.
Collapse
Affiliation(s)
- Yu Lei
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qing Tong
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xinyu Zhang
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Hongshi Sang
- National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074, China
| | - An Ji
- Institute of Semiconductors, Chinese Academy of Science, Beijing 100083, China
| | - Changsheng Xie
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
| |
Collapse
|
15
|
Hsu CJ, Liao CH, Chen BL, Chih SY, Huang CY. Polarization-insensitive liquid crystal microlens array with dual focal modes. OPTICS EXPRESS 2014; 22:25925-25930. [PMID: 25401625 DOI: 10.1364/oe.22.025925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate a liquid crystal (LC) microlens array (MLA) fabricated by LCs possessing negative dielectric anisotropy, in conjunction with a cell with a three-electrode structure. The presented LC MLA is polarization-insensitive and can be operated in both concave and convex modes. The shortest focal length of the LC MLA is -2.54 and 2.22 mm in concave and convex mode, respectively. Disclination lines that are usually observed in conventional hole-patterned LC lens can also be avoided because of the vertical alignment treatment of LCs.
Collapse
|
16
|
Lin SH, Huang LS, Lin CH, Kuo CT. Polarization-independent and fast tunable microlens array based on blue phase liquid crystals. OPTICS EXPRESS 2014; 22:925-930. [PMID: 24515052 DOI: 10.1364/oe.22.000925] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This work investigates a polarization-independent and fast response microlens array. This array is composed of a concave polymer microlens array and blue phase liquid crystals (BPLCs). The microlens array can be either positive or negative, depending on the birefringence of the BPLCs. The experimental results show that the microlens array is fast switched between positive and negative focal lengths via controlling the electric fields, and the response time is a few hundred microseconds. Additionally, the focusing efficiency is independent of the polarization of the incident light.
Collapse
|
17
|
Dong Liang, Qiong-Hua Wang. Liquid Crystal Microlens Array Using Double Lenticular Electrodes. ACTA ACUST UNITED AC 2013. [DOI: 10.1109/jdt.2013.2260722] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
18
|
Liu Y, Li Y, Wu ST. Polarization-independent adaptive lens with two different blue-phase liquid-crystal layers. APPLIED OPTICS 2013; 52:3216-3220. [PMID: 23669832 DOI: 10.1364/ao.52.003216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 04/15/2013] [Indexed: 06/02/2023]
Abstract
An adaptive microlens structure is proposed using two polymer-stabilized blue-phase liquid-crystal layers whose Kerr constant is largely mismatched. This device exhibits several favorable features, such as polarization independence, simple structure, and good parabolic phase profile. Its applications for 2D/3D switchable displays and other photonic devices are emphasized.
Collapse
Affiliation(s)
- Yifan Liu
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA
| | | | | |
Collapse
|
19
|
Ren H, Xu S, Liu Y, Wu ST. Switchable focus using a polymeric lenticular microlens array and a polarization rotator. OPTICS EXPRESS 2013; 21:7916-7925. [PMID: 23571883 DOI: 10.1364/oe.21.007916] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate a flat polymeric lenticular microlens array using a mixture of rod-like diacrylate monomer and positive dielectric anisotropy nematic liquid crystal (LC). To create gradient refractive index profile in one microlens, we generate fringing fields from a planar top electrode and two striped bottom electrodes. After UV stabilization, the film is optically anisotropic and can stand alone. We then laminate this film on a 90° twisted-nematic LC cell, which works as a dynamic polarization rotator. The static polymeric lenticular lens exhibits focusing effect only to the extraordinary ray, but no optical effect to the ordinary ray. Such an integrated lens system offers several advantages, such as low voltage, fast response time, and temperature insensitivity, and can be used for switchable 2D/3D displays.
Collapse
Affiliation(s)
- Hongwen Ren
- Department of polymer Nano-Science and Tech., Chonbuk National University, Jeonju, Jeonbuk, 561-756, South Korea.
| | | | | | | |
Collapse
|
20
|
Kuo CH, Chien WC, Hsieh CT, Huang CY, Jiang JJ, Li YC, Chen MF, Hsieh YP, Kuo HL, Lin CH. Influence of pretilt angle on disclination lines of liquid crystal lens. APPLIED OPTICS 2012; 51:4269-4274. [PMID: 22772097 DOI: 10.1364/ao.51.004269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 05/18/2012] [Indexed: 06/01/2023]
Abstract
This article investigates the effect of pretilt angle on disclination lines of liquid crystal (LC) lenses. When the pretilt angle of LCs is higher than 7°, the disclination lines are reduced and are moved to the boundary of the LC lens. The disclination lines at the boundary do not influence the focused beam profile of the LC lens. As the pretilt angle of LCs further increases, the disclination lines at the boundary become almost invisible. However, the interference rings become asymmetrical. The response time of an LC lens with a pretilt angle higher than 7° is ∼60% of the conventionally homogeneous LC lens. This value is a result of the decrease in the rotation angle of the LCs and the reduced disclination lines.
Collapse
Affiliation(s)
- Chia-Hao Kuo
- Graduate Institute of Photonics, National Changhua University of Education, Changhua 500, Taiwan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Lin YH, Chen MS. A Pico Projection System With Electrically Tunable Optical Zoom Ratio Adopting Two Liquid Crystal Lenses. ACTA ACUST UNITED AC 2012. [DOI: 10.1109/jdt.2012.2185215] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
22
|
Zhao X, Liu C, Zhang D, Luo Y. Tunable liquid crystal microlens array using hole patterned electrode structure with ultrathin glass slab. APPLIED OPTICS 2012; 51:3024-3030. [PMID: 22614606 DOI: 10.1364/ao.51.003024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 04/05/2012] [Indexed: 06/01/2023]
Abstract
A configuration of hole patterned electrode liquid crystal microlens array with an ultrathin glass slab was fabricated. To reduce the fringing electric field effect and avoid the occurrence of disclination lines, an ultrathin glass slab was introduced between the patterned electrode and liquid crystal layer. The glass slab thickness played an important role in effecting the optical performance of the liquid crystal microlens array. An optimum thickness of 30 μm was selected employing numerical simulation method. Using this method, we demonstrated a microlens array that greatly improved the phase profile and focus power. The dynamic focal range of the liquid crystal microlens array may extend from <1.2 mm to >8 mm and the minimum diameter of the focus spot could be as small as 15 µm.
Collapse
Affiliation(s)
- Xiangjie Zhao
- Institute of Fluid Physics, China Academy of Engineering Physics, MianYang, China.
| | | | | | | |
Collapse
|
23
|
Li Y, Liu Y, Li Q, Wu ST. Polarization independent blue-phase liquid crystal cylindrical lens with a resistive film. APPLIED OPTICS 2012; 51:2568-2572. [PMID: 22614475 DOI: 10.1364/ao.51.002568] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 03/01/2012] [Indexed: 06/01/2023]
Abstract
We propose a new electrode design for polarization-independent cylindrical lens using a polymer-stabilized blue phase liquid crystal (BPLC). The top electrode is coated with a transparent and resistive film to generate linearly varying electric potential from center to edge; while the bottom iridium tin oxide electrode has a constant potential. Therefore, the vertical electric field across the BPLC layer varies linearly over the lens aperture and a desired parabolic phase profile is obtained automatically according to the Kerr effect. Simulation results show that this simple device is polarization independent and it has parabolic-like phase profile in a large tuning range.
Collapse
Affiliation(s)
- Yan Li
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA
| | | | | | | |
Collapse
|
24
|
Huang SY, Tung TC, Jau HC, Liu JH, Fuh AYG. All-optical controlling of the focal intensity of a liquid crystal polymer microlens array. APPLIED OPTICS 2011; 50:5883-5888. [PMID: 22015416 DOI: 10.1364/ao.50.005883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The current work demonstrates a liquid crystalline polymer microlens array (LCP MLA) with an all-optically tunable and multistable focal intensity through photochemical phase transition. The operational mechanism of the optical tuning is associated with the photoisomerization effect. The proposed LCP MLA device has a focusing unit based on a birefringence LCP and a tuning unit with a light responsive material to control the polarization state of the incident probe beam. The optically variable refractive indices of LCP enable a positive or negative MLA that can control the polarization of incident light to be realized.
Collapse
Affiliation(s)
- San-Yi Huang
- Institute of Electro-Optical Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | | | | | | | | |
Collapse
|
25
|
Lee CT, Li Y, Lin HY, Wu ST. Design of polarization-insensitive multi-electrode GRIN lens with a blue-phase liquid crystal. OPTICS EXPRESS 2011; 19:17402-17407. [PMID: 21935105 DOI: 10.1364/oe.19.017402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report the design and simulation results of an adaptive GRIN lens based on multi-electrode addressed blue phase liquid crystal. A high dielectric constant layer helps to smoothen out the horizontal electric field and reduce the operating voltage. Such a GRIN lens is insensitive to polarization while keeping parabolic phase profile as the focal length changes.
Collapse
Affiliation(s)
- Chao-Te Lee
- College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA
| | | | | | | |
Collapse
|
26
|
Li Y, Wu ST. Polarization independent adaptive microlens with a blue-phase liquid crystal. OPTICS EXPRESS 2011; 19:8045-8050. [PMID: 21643053 DOI: 10.1364/oe.19.008045] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A new polarization-independent and fast-response adaptive microlens array using a polymer-stabilized blue phase liquid crystal is proposed. With a curved top electrode and planar bottom electrode, gradient electric fields are generated and lens-like phase profile obtained. Optimization process leads to an ideal parabolic phase profile for suppressing spherical aberration.
Collapse
Affiliation(s)
- Yan Li
- College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA
| | | |
Collapse
|
27
|
Feng GH, Chou YC. Flexible meniscus/biconvex lens system with fluidic-controlled tunable-focus applications. APPLIED OPTICS 2009; 48:3284-3290. [PMID: 19543333 DOI: 10.1364/ao.48.003284] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Controlled injection of fluid into a flexible lens chamber has previously produced tunable spherical lenses with spherical aberration problems. This paper presents a novel fluidic-controlled meniscus/biconvex lens system with relatively low distortion. The lens fabrication method is described and manufactured lenses are characterized for different processing parameters. Images captured through one of our lenses for a range of different pressures are presented. A change in focal length of five times (19.1-80.8 cm) is demonstrated. The focal length shows a quadratic relation to the applied pressure (0-5 kPa). For the simple prototype lens, distortion is less than 5% and relative illumination is above 0.74 by ZEMAX analysis.
Collapse
Affiliation(s)
- Guo-Hua Feng
- Department of Mechanical Engineering, National Chung Cheng University, Chiayi 621, Taiwan.
| | | |
Collapse
|